1. Field of the Invention
The present invention relates generally to a member for connecting articles, and more particularly to a threaded member, which is capable of detecting the tension of the threaded member when tightening an article with the threaded member.
2. Description of the Related Art
Bolts and nuts are often seen threaded members and widely used in various fields for fixedly connecting two or more articles with each other. By means of tightening the bolts, the articles can be fixed with each other.
Many parts of sophisticated equipment and large-scale buildings such as bridges, reservoirs and hardware of power plants are connected by threaded members. Such sophisticated equipment and buildings not only require that the parts be fixedly connected together, but also require that the parts be tightened by precise tightening force. In the case that the threaded members are under-tightened or over-tightened, not only the design requirement cannot be satisfied, but also the use effect and security of the buildings and equipment will be affected.
In order to find the tightening force/tightening torque applied to the threaded member for tightening an article, conventionally, a sensor is disposed on the bolt. When the article is tightened with a bolt, the sensor can detect the deformation of the bolt to achieve the tightening force/tightening torque applied to the bolt. In this case, an operator can control the tightening force applied to the bolt.
The above technique is able to detect the deformation of the threaded member to find the tightening force applied to the threaded member according to the relationship between the deformation and the tightening force. The present invention provides another detection technique for detecting the tightening extent of the threaded member.